More atomic functions please

[Piotr Wyderski]

Jakub Jelinek wrote:

>  /* X86_TUNE_USE_INCDEC */
>  ~(m_PENT4 | m_NOCONA | m_CORE2I7 | m_GENERIC | m_ATOM),
>
> So, if you say -mtune=bdver1 or -mtune=k8, it will generate incl,
> if addl is better (e.g. on Atom incl is very bad compared to addl $1),
> it will generate it.

Why is lock inc/dec worse than add/sub on Core2I7?
The only difference I know of is the way the carry flag
is handled.

  Best regards,
  Piotr Wyderski